Grit n shit in coolant system

[therefused]

Hi had a pipe burst on the m6 yesterday dumped all my coolant lol. Was the pipe from the bulk head to the back of the block, had to cut the pipe and slip it back on, bit awkward but sorted now.

Anyway wen the last of the water poured out the pipe it was full of rust and grit, iv done a coolant change before.

What's the best way of flushing the system properly? Can you get a rust eating solution of some type?

Am I best taking the thermostat out, reconnecting the housing, n opening the radiator drain plug. Putting a hosepipe in the header tank and just run it through with the engine running?

Wana try me best clear all the grit and silt

[Ben]

That sounds like a blocked/partially blocked heater matrix. I doubt there's really much grit elsewhere. You can try flushing it by blasting a hose through the matrix, but be prepared to have to change the matrix. Changing it would be the best option and if you do it yourself will cost under 30 quid.

[ozonehostile]

As i said in another heater related post, but if your matrix is starting to get clogged it might be possible to try and clear it out a bit to put off having to change it for a couple of months. if its only got a small build up this technique might work for you

sounds like it could be a clogged heater matrix. easiest way to check is to follow the pipes from the engine into the matrix, check if both sides are hot. if it turns out that one side is hot and the other cold, you could try disconnecting the hoses where they go into the bulkhead and switching them round the other way and running the engine at about 2k rpm for 5 minutes, this is usually enough to clear out a small blockage as the reverse flow dislodges some build up. make sure you change the hoses back the right way around after and keep the coolant level topped up while bleeding any air out of the system.
The hoses can be a bit of a bastard to get off as they have those retainer clip things holding them on, I found a pair of needlenose molegrips and a lever bar very useful to get them off.
Hope this helps

[Ben]

Why would you try and clear it like that though? If it does unblock then all the grit is going to stay in your coolant system.

If you take both pipes off the engine and put a hose in one of them and the other in a bucket then any grit will end up in the bucket.

[ozonehostile]

Why would you try and clear it like that though? If it does unblock then all the grit is going to stay in your coolant system.

If you take both pipes off the engine and put a hose in one of them and the other in a bucket then any grit will end up in the bucket.

I flushed all the crap out of the matrix out while i was bleeding the air out of the system, disconnect the hose coming out of the thermostat housing where it joins back onto a metal pipe, disconnect it but hold so that there is still some water flowing into the head but with let most of it flow out, keep filling the rad up until the water flowing out is as clear as its going to get.